Boots' tie-up with US drugstore giant Walgreens, clinched last year, had fuelled worries the British retailer might start taking on the habits of the American chain, which stocks cigarettes, alcohol and sweets.

But Mr Pessina was keen to stress that the deal, which saw Walgreens take a 45pc stake in Boots' parent company in June last year, would lead to no such thing.

"The US market and European market are completely different," he said. "We have to do what our customers want us to do.

"It would be absolutely inconceivable for a pharmacy [in Europe] to sell cigarettes."

Although it is commonplace for US drugstores to stock cigarettes, the apparent hypocrisy does not go unchallenged. Criticism of Walgreens' mixed offering in particular has stepped up in recent months as the chain moves to expand in-store health check-ups by medical professionals.

However Walgreens, which is likely to buy the whole of Boots within three years, an option which was left open in the tie-up deal, argues that it needs to meet demand for cigarettes to stay competitive.

Mr Pessina's assurances came as Boots posted a 21pc rise in pre-tax profits to £837m despite a 2.6pc fall in revenue, as the group looked to cut costs in the face of weakening demand from its dominant European market.

A number of patent expirations, such as that for cholesterol-fighting drug Lipitor, also eroded sales this year as cheaper generic versions entered the market, the company said.

The biggest profit growth was seen in the group's health and beauty division, which enjoyed a boost from strong demand for anti-aging serums, which Boots said was its best-selling beauty product.